#include <iostream>
using namespace std;
int main()
{
    cout << "正方形:" << endl;
    ;
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 10; j++) {
            cout << "* ";
        }
        cout << endl;
    }
    cout << "三角形1:" << endl;
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j <= i; j++) {
            cout << "* ";
        }
        cout << endl;
    }
    cout << "三角形2:" << endl;
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 10 - i; j++) {
            cout << "* ";
        }
        cout << endl;
    }
    cout << "三角形3:" << endl;
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 10; j++) {
            if (j >= 9 - i) {
                cout << "* ";
            } else {
                cout << "  ";
            }
        }
        cout << endl;
    }
    cout << "三角形4:" << endl;
    for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 10; j++) {
            if (j >= i) {
                cout << "* ";
            } else {
                cout << "  ";
            }
        }
        cout << endl;
    }
    return 0;
}
